diff --git a/ph-xml/src/main/java/com/helger/xml/XMLFactory.java b/ph-xml/src/main/java/com/helger/xml/XMLFactory.java
index 72a4d8ef5..9e07c4bce 100644
--- a/ph-xml/src/main/java/com/helger/xml/XMLFactory.java
+++ b/ph-xml/src/main/java/com/helger/xml/XMLFactory.java
@@ -134,32 +134,25 @@ private static void _setFeature (@Nonnull final DocumentBuilderFactory aFactory,
     }
   }
 
-  /**
-   * Create a new {@link DocumentBuilderFactory} using the defaults defined in
-   * this class ({@link #DEFAULT_DOM_NAMESPACE_AWARE},
-   * {@link #DEFAULT_DOM_VALIDATING} ,
-   * {@link #DEFAULT_DOM_IGNORING_ELEMENT_CONTENT_WHITESPACE},
-   * {@link #DEFAULT_DOM_EXPAND_ENTITY_REFERENCES},
-   * {@link #DEFAULT_DOM_IGNORING_COMMENTS} and
-   * {@link #DEFAULT_DOM_COALESCING}.).
-   *
-   * @return Never <code>null</code>.
-   */
-  @Nonnull
-  public static DocumentBuilderFactory createDefaultDocumentBuilderFactory ()
+  public static void defaultCustomizeDocumentBuilderFactory (@Nonnull final DocumentBuilderFactory aFactory)
   {
-    // Secure processing is enabled by default since JDK 8
-    final DocumentBuilderFactory aFactory = DocumentBuilderFactory.newInstance ();
+    /*
+     * Secure processing is enabled by default since JDK 8. See class
+     * "com.sun.org.apache.xerces.internal.jaxp.DocumentBuilderFactoryImpl"
+     * field "fSecure" is initially "true". However, if someone uses an external
+     * XML parser library (like Xerces) it might be disabled.
+     */
+    _setFeature (aFactory, EXMLParserFeature.SECURE_PROCESSING, true);
     _setFeature (aFactory, EXMLParserFeature.DISALLOW_DOCTYPE_DECL, true);
     _setFeature (aFactory, EXMLParserFeature.EXTERNAL_GENERAL_ENTITIES, false);
     _setFeature (aFactory, EXMLParserFeature.EXTERNAL_PARAMETER_ENTITIES, false);
+    _setFeature (aFactory, EXMLParserFeature.LOAD_EXTERNAL_DTD, false);
     aFactory.setNamespaceAware (DEFAULT_DOM_NAMESPACE_AWARE);
     aFactory.setValidating (DEFAULT_DOM_VALIDATING);
     aFactory.setIgnoringElementContentWhitespace (DEFAULT_DOM_IGNORING_ELEMENT_CONTENT_WHITESPACE);
     aFactory.setExpandEntityReferences (DEFAULT_DOM_EXPAND_ENTITY_REFERENCES);
     aFactory.setIgnoringComments (DEFAULT_DOM_IGNORING_COMMENTS);
     aFactory.setCoalescing (DEFAULT_DOM_COALESCING);
-
     try
     {
       aFactory.setXIncludeAware (DEFAULT_DOM_XINCLUDE_AWARE);
@@ -168,6 +161,24 @@ public static DocumentBuilderFactory createDefaultDocumentBuilderFactory ()
     {
       // Ignore
     }
+  }
+
+  /**
+   * Create a new {@link DocumentBuilderFactory} using the defaults defined in
+   * this class ({@link #DEFAULT_DOM_NAMESPACE_AWARE},
+   * {@link #DEFAULT_DOM_VALIDATING} ,
+   * {@link #DEFAULT_DOM_IGNORING_ELEMENT_CONTENT_WHITESPACE},
+   * {@link #DEFAULT_DOM_EXPAND_ENTITY_REFERENCES},
+   * {@link #DEFAULT_DOM_IGNORING_COMMENTS} and
+   * {@link #DEFAULT_DOM_COALESCING}.).
+   *
+   * @return Never <code>null</code>.
+   */
+  @Nonnull
+  public static DocumentBuilderFactory createDefaultDocumentBuilderFactory ()
+  {
+    final DocumentBuilderFactory aFactory = DocumentBuilderFactory.newInstance ();
+    defaultCustomizeDocumentBuilderFactory (aFactory);
     return aFactory;
   }
 
@@ -440,6 +451,18 @@ private static void _setFeature (@Nonnull final SAXParserFactory aFactory,
     }
   }
 
+  public static void defaultCustomizeSAXParserFactory (@Nonnull final SAXParserFactory aFactory)
+  {
+    _setFeature (aFactory, EXMLParserFeature.SECURE_PROCESSING, true);
+    _setFeature (aFactory, EXMLParserFeature.DISALLOW_DOCTYPE_DECL, true);
+    _setFeature (aFactory, EXMLParserFeature.EXTERNAL_GENERAL_ENTITIES, false);
+    _setFeature (aFactory, EXMLParserFeature.EXTERNAL_PARAMETER_ENTITIES, false);
+    _setFeature (aFactory, EXMLParserFeature.LOAD_EXTERNAL_DTD, false);
+    aFactory.setNamespaceAware (DEFAULT_SAX_NAMESPACE_AWARE);
+    aFactory.setValidating (DEFAULT_SAX_VALIDATING);
+    aFactory.setXIncludeAware (DEFAULT_SAX_XINCLUDE_AWARE);
+  }
+
   @Nonnull
   public static SAXParserFactory createDefaultSAXParserFactory ()
   {
@@ -454,12 +477,7 @@ public static SAXParserFactory createDefaultSAXParserFactory ()
       // Java 8 method - see #41
       aFactory = SAXParserFactory.newInstance ();
     }
-    _setFeature (aFactory, EXMLParserFeature.DISALLOW_DOCTYPE_DECL, true);
-    _setFeature (aFactory, EXMLParserFeature.EXTERNAL_GENERAL_ENTITIES, false);
-    _setFeature (aFactory, EXMLParserFeature.EXTERNAL_PARAMETER_ENTITIES, false);
-    aFactory.setNamespaceAware (DEFAULT_SAX_NAMESPACE_AWARE);
-    aFactory.setValidating (DEFAULT_SAX_VALIDATING);
-    aFactory.setXIncludeAware (DEFAULT_SAX_XINCLUDE_AWARE);
+    defaultCustomizeSAXParserFactory (aFactory);
     return aFactory;
   }
 
@@ -482,19 +500,26 @@ private static void _setFeature (@Nonnull final TransformerFactory aFactory,
     }
   }
 
+  public static void defaultCustomizeTransformerFactory (@Nonnull final TransformerFactory aFactory)
+  {
+    if (false)
+    {
+      // This prevents to use XSLT includes
+      _setFeature (aFactory, EXMLParserFeature.SECURE_PROCESSING, true);
+    }
+    _setFeature (aFactory, EXMLParserFeature.DISALLOW_DOCTYPE_DECL, true);
+    _setFeature (aFactory, EXMLParserFeature.EXTERNAL_GENERAL_ENTITIES, false);
+    _setFeature (aFactory, EXMLParserFeature.EXTERNAL_PARAMETER_ENTITIES, false);
+    _setFeature (aFactory, EXMLParserFeature.LOAD_EXTERNAL_DTD, false);
+  }
+
   @Nonnull
   public static TransformerFactory createDefaultTransformerFactory ()
   {
     try
     {
       final TransformerFactory aFactory = TransformerFactory.newInstance ();
-      if (false)
-      {
-        // Not needed for Java 11
-        _setFeature (aFactory, EXMLParserFeature.DISALLOW_DOCTYPE_DECL, true);
-        _setFeature (aFactory, EXMLParserFeature.EXTERNAL_GENERAL_ENTITIES, false);
-        _setFeature (aFactory, EXMLParserFeature.EXTERNAL_PARAMETER_ENTITIES, false);
-      }
+      defaultCustomizeTransformerFactory (aFactory);
       return aFactory;
     }
     catch (final TransformerFactoryConfigurationError ex)